Automatic reclosing circuit breaker



April 17, I934. R. s. SEESE 1,954,849

AUTOMATIC RECLOSING CIRCUIT BREAKER Filed Aug. 27', 1950 3 Sheets-Sheetl I INVENTOR ATTORNEYS April 17, 1934.

a a 22 42 94 y R. S. SEESE AUTOMATIC RECLOSING CIRCUIT BREAKER FiledAug. 27, 1930 3 Sheets-Sheet 3 INVENTOR flAEr/S 59659) ATTO R N EYSPatented Apr. 17, 1934 PATENT -OFFECE 1,954,849 AUTOMATIC aacnosnvc.omourr BREAKER Robert S. Scene, Detroit, Mich. Application August 27,1930, Serial No. 478,007

11 Claims. (Cl. 175-294) My invention relates to mechanism "for theautomatic operation of a circuit breaker.

The object'of my invention is to provide a simple, inexpensive, andreliable device which will open a circuit breaker upon the occurrence ofabnormal conditions in circuit, reclose the circuit breaker after apredetermined time interval, repeat the above operations if the abnormalconditions continue, and finally, if the abnormal conditions persist,leave the breaker in open position after a predetermined number oi.opening and closing operations.

A further object of my invention is to provide a device, as describedabove, without any relay or relays to control the reclosing function, orto limit the number of reclosing operations, but with mechanicalfeatures to control such reclosing and limiting functions, thusdecreasing the liability of failure.

A further object of my invention, is to provide a device, as describedabove, in which the reclosing mechanism, the timing mechanism whichcontrols the reclosing functiomthe limiting mechanism which limits thenumber of reclosures and, if desired, a resetting mechanism which resetsthe timing and limiting mechanism to their initial positions should theabnormal conditions in the circuit disappear before the limitingmechanism has functioned are all driven from a common 30 motor.

Other objects will appear in the further and more detailed considerationof the invention.

A circuit breaker is included in an electric circuit in order tointerrupt such circuit when desired. An automatic circuit breaker,so-called, is designed to open automatically when overload or shortcircuit conditions of predetermined intensity appear in its circuit. Anautomatic reclosing circuit breaker not only opens automatically, asjust described, but is provided with means for reclosing automaticallyafter a predetermined time interval, .on the assumption that theabnormal conditions causing the breaker to open will have disappeared.If such conditions have not disappeared when the breaker recloses,

it will again open automatically, and again reclose after a certainelapsed time. Additional trippings and reclosures will occur as long asthe abnormal circuit conditions persist, unless some limiting device isprovided to limit the reclosures to a predetermined number. Usuallythere is a means of restoring the limiting device to its initialposition should the abnormal circuit conditions disappear before thepredeter mined number of reclosures has been made.

Such restoring. means will enable the circuit breaker to reclose thefull predetermined number of times, should any abnormal circuitcondition appear subsequently. If, however, the abnormal conditionspersist until the full predetermined 00 number of reclosures has beenmade, the limiting device will cause the circuit breaker to remain inopen position until it is restored manually, at which time the limitingdevice can be returned to its initial position. No invention is claimedfor the elements described in this paragraph, the automatic reclosingcircuit breaker with provision for locking open after a predeterminednumber of reclosures having been described fully in Thomson Patent No.508,652 dated November 14, 1892. The invention about to be described isan improvement on existing methods of accomplishing these results, andeliminates certain undesirable features.

It is at once obvious that, from its very nature, the fully automaticreclosing circuit breaker will usually operate unobserved. Since it isdesigned to operate in emergencies, or under abnormal conditions, it isimperative that its operation be as reliable as possible. It isessential, therefore, that any delicate parts, such as small timingcontacts, relays, dashpots, coil windings apt to be affected bylightning or abnormal voltages be omitted wherever possible, or at leastreplaced by sturdy parts not likely to cause trouble. In the inventionunder consideration, reliance is placed on simple mechanical parts noteasily subject to climatic or circuit conditions, and operated by acommon driving means of suflicient power to perform the variousfunctions positive- 1y, even after long periods of idleness. Theemployment of common driving means, moreover, gives propersynchronization of the various elements of the mechanism where this isdesirable.

Of the accompanying drawings, which serve to show schematically in sideelevation my mechanical means for automatically-opening and closing acircuit breaker for limiting the number of reclosures on any single caseof load circuit trouble, and for resetting the reclosure limitingdevice,

Figure 1 indicates the initial or "closed position of the circuitbreaker and of its operating mechanism;

Fig. 2 shows the approximate position of parts just after circuitbreaker is thrown into open position;

Fig. 3 also shows the breaker in open position just prior to beingreclosed for the first time,

as indicated by Fig. 4 which shows the position of mechanism before asecond opening of breaker takes place;

Fig. 5 shows the breaker locked in open position after the predeterminednumber of reclosures have taken place and before the mechanism has beenreturned to its normal or initial posi-' tion, as indicated in Fig. 1.

Similar parts of all drawings are indicated by the same referencefigures, as follows:

With the exception of current transformers 5, tripping coils 30, andmotor 24, no electrically energized elements are employed in connectionwith my breaker operating and controlling mechanism, which presents acombination of purely mechanical elements actuated from a powerfulcommon source of motion, greatly decreasing the liability of failure.

As indicated by the drawings, an electric generator 1 supplies currentto an external circuit 2 through a circuit breaker 3 to a load circuit 4wherein current transformers 5 are placed. The circuit breaker 3,normally biased to open by gravity and by pull of spring 6, is held inclosed position by a toggle joint 7, one end 8 of the joint beingattached to bell-crank lever 9, while the other end 10 is connected tothe end of a lever 11 held against upward movement by a stop 12. One endof lever 11 is bent upwardly to ride lightly on the circumferentialsurface of a timing disk 14 to which a concentrically-disposed notchedactuating wheel 15 is fixedly attached. This wheel is normally moved ina clockwise direction against the pull of spring 16, while anoppositely-disposed notched resetting wheel 1'7 is moved in a counterclockwise direction against the pull of a spring 18. Both wheels areadapted to be independently rotated by the pawl 19 carried by a rodpivotally attached to lever 20, a retracting spring 21 normally holdinglever 20 in contact with stop 22. I

The breaker closing mechanism comprises a cam member 23 adapted to berotated in clockwise direction by the motor 24, which is driven from aconventionally illustrated source of energy 25, the motor circuit beingclosed through switch 26 when the breaker 3 opens. When overloading ofpredetermined intensity occurs, a pivotally-mounted hammer-like member27, normally held in inactive position by latch member 28. is released,energization of the tripping coils 30 by current delivered thereto bythe-current transformers 5 serving to pull the latch 28 away from theholding end of lever 27, which is then quickly forced upwardly by thespring 29, striking toggle '7, breaking it and thus allowing breaker 3to open under the influence of gravity and pull of spring 6.

With the line protected by the circuit breaker in its normal condition,the elements represented by the schematic showing will be in thepositions of Fig. 1, in which the circuit-breaker 3 is closed and heldin such position by the linkage 11 which includes the toggle '7. Sinceboth make and break points 26 and 3'7 are open, the motor circuit isinactive. Timing disc 14 and its wheel 15 are in the inactive position,having been returned by its spring at the close of the previous advanceof wheel 17 by pawl 19 through the release action of latch 36, pawl 19continuing to hold wheel 17 in such completed position with spring 18under tension.

Assuming an abnormal condition developing in the line being protected,the trip mechanism represented by coils 30 are made active to releaselatch 28, whereupon spring 29 causes hammer 27 to move forcibly intocontact with the toggle and break the latter, thus permitting thecircuit breaker to move to open position, the support therefor providedby the linkage being made inactive as a support. The movement of the circuit breaker to open position operates arm 9 and through it, pawl 19 isshifted into contact with wheel 15, releasing wheel 1'7 and permittingthe latter to return to its inactive position by action of spring 18,the movement of the pawl 19 having released a latch 38 from engagementwith wheel 1'7.

The movement of the circuit breaker to its open position permits thelatter to close make and break point 26 of the motor circuit, asindicated in Fig. 2, thus beginning operation of the motor 24 and cam 23which, during its initial rotation returns hammer 27 to its latchedposition out of the path of travel of cam 23. Also, this movement of thecam, and each succeeding rotation, causes it to contact with and movearm 20 on its pivot against the tension of spring 21, thus moving pawl19 downward a distance of a stepwhich may be one or more teeth of wheelI 15-50 that when the cam passes the arm, spring 21 serves to move thepawl upwardly and thus advance wheel 15 one step from its inactiveposition. This action continues with each cam rotation until the advanceof wheel 15 brings the first of the slots 31 of the timing disk 14 intoposition where the upwardly-turned end 13 of the linkage is free toenter the slot, whereupon the weight of the collapsed linkage causes thelinkage to collapse downwardly as permitted by the end 13 entering theslot, as indicated in Fig. 3, thus bringing the linkage also within thepath of travel of 'cam 23 and at the same time straightening the toggle.As a result, the cam 23 during its rotation, contacts with-the linkageand raises it to the position of Fig. 4, thus moving the lower end ofhell crank lever 9 in a direction to reclose the circuit breaker, and atthe same time shift pawl 19 into engagement with wheel 1'7.

However, the parts are so arranged that pawl 19 remains in engagementwith the tooth of wheel 15' sufliciently long as to permit spring 21 togive an upward impulse to pawl 19, after the cam has released member 20,this taking place before the cam disengages the linkage, the directionof movement of end 13 being such that advance of wheel 15 can be hadwithout damaging of parts during upward travel of the linkage after thecam has left arm 20. Hence, wheel 15 will have been advanced one step,so that the end 13 does not re-enter the slot 31 when the cam hasshifted the linkage to the position of Fig. 4.

At this point it should be noted that the motor circuit also includes asecond make and break point represented by a pivoted arm 37 connected toone side of the circuit and extending into the path of travel of a pin4'7 carried by disk 14, said arm 3'7 co-operating with a contactconnected with the other side of the motor circuit. The two points 26and 3'7 thus indicate a pair of make and break points in the motorcircuit with the points arranged in parallel. In Fig. 1, arm 37 is shownas held out of contact by pin 4'7, so that under normal operatingconditions, both make and break points are broken. When, however, wheel15 begins its advance, pin 47 is moved from its supporting position toarm 3'7, the latter then moving to close this second make and breakpoint, this point remaining closedand completing the motor circuitthroughout the period during which wheel 15 and timing disc 14 remainout of the inactive position of Fig. 1.

Hence, when the circuit breaker has been reclosed by the movement of thelinkage by the cam, as above describedthus opening the first make andbreak point 26, the motor circuit remains complete because of the closedsecond point 37. Hence, the motor continues in operation and cam 23continues its operations on arm 20 and providing impulses to pawl 19;since the latter is now in contact with wheel 17, the latter willadvance, a latch 38, heretofore referred to, being held in contact withthe wheel by spring 41, to prevent return movement of the wheel underthe action of spring 18. If the return of the circuit breaker finds theline free from the abnormality, wheel 17 will continue to advancestep-by-step until its rotation brings a member 35 carried by the wheelinto engagement with a latch 36-normally active to prevent retrogrademovement of wheel 15 by the action of a spring 42whereupon member 35operates latch 36 to release wheel 15, the latter then being free toreturn to its inactive position through the action of spring 16, theclose of this movement causing pin 47 to raise arm 37 and break themotor circuit and thus stop the motor.

If, however, the return of the circuit breaker demonstrates that theabnormality persists, its presence will again render the trippingmechanism active to release latch 28, with the result that the toggle isagain brokenand the cycle of operations described again repeated butwith certain changed conditions. Since the repetition of the cyclebegins before wheel 17 has completed its revolution, wheel 15 remains inthe position it occupied when pawl 19 was previously released fromengagement therewithbeing held by latch 36and hence make and break point3'7 is still closed with the motor operating. Breaking of the toggleshifts pawl 19 into engagement with wheel 15, the movement releasinglatch 38 from engagement with wheel 17 through engagement of arm 39 withpin 40 of the latch, with the result that wheel 1'7 is free to returnunder the action of spring 18, the return movement continuing untilmember 35 engages stop 46, this position representing the inactiveposition of wheel 17, the latter thus being in position to again advanceto make the complete revolution previously referred to. It should benoted that wheel 17 can make such complete revolution only when thecircuit breaker remains in its closed position sufliciently long topermit the wheel step-by-step advance to complete the revolution; if theadvance is interrupted by the opening of the circuit breaker, the wheelautomatically returns to its inactive position as above indicated, thusbeing ready to begin such advance for the complete distance. The wheelthus presents a definite time characteristic made manifest only when theline is free of abnormalities for a period designed to be sumcient toindicate stability of the line after temporary abnormality conditions.At the close of such complete period, it functions to re-set theoperating system by opening the way to a return of the timing means toits inactive position and the breaking of the motor circuit at 37.

Another distinction is in the position of wheel 15, which, as beforepointed out, has not returned to its inactive position-wheel 1'7 nothaving completed its revolution before the circuit breaker again opened.The end 13 of the linkage rides on the circular face of disk 14' beyondthe first slot 31, so that as cam 23 continues to set up the pawlimpulses by its actuation of arm 20, the engagement of pawl 19 withwheel 15produced by the breaking of the togglecauses the wheel 15 toagain advance step-bystep until the second slot 31 comes into positionto receive the end 13, whereupon the previous circuit breaker re-closingcycle again takes place, as before described, pawl 19 being shifted towheel 1'7 to again begin the advance of the latter; the reclosing actionremoves end 13 from the slot, with the step advance of wheel 15, asbefore described, thus leaving the parts ready for the final re-settingaction if the circuit breaker remains closed sufiiciently long to permitwheel 1'? to make it: complete revolution.

If however, the abnormality persists, the cycle referred to is repeatedwith end 13 passing into the third slot 31, as wheel 15 is furtheradvanced, wheel 17 having again returned to inactive position, thussetting the mechanism for a third reclosing of the circuit breaker withthe wheel 17 again beginning its advance. The time disk 14, as shown, isdesigned to permit three reclosures of the circuit breaker, and sincethe spacing of the slots 31 represents a definite time characteristicdue to the conditions of the stepby-step advance of wheel 15, thereclosures well have a definite interval characteristic. It isconsidered with this arrangement that three reclosures would besufficient to demonstrate the presence of a persistent abnormality whichrequired manual correction, and hence the disclo sure simply indicatesthe three slots.

Should the reclosure, however, disclose the presence of a continuedabnormality thus indicating a persistent condition, the succeedingdevelopment of the cycle by breaking the toggle causesadvance of wheel15 until a stop 33 thereon contacts with a stop 34, thus preventingfurther advance of wheel 15, pawl 19 then idling until the systemreceives manual attention, arm 37 retaining the motor circuit activesince wheel 15 prevents collapse of the linkage to the position of Fig.3, and prevents activity of pawl 19 with wheel 17, thus preventingdevelopment of the cycle which would release latch 36 and permit wheel17 to return wheel 15 to its starting or inactive position, essential ifarm 3'7 is to open the motor circuit. The circuit breaker thereforeremains open and the motor and cam continue their rotations awaiting themanual activities to restore the line conditions to normality and resetthe operating mechanisms.

The schematic representation of pawl 19 in this manner indicates one ofthe characteristics of the invention, viz: the advancing activity ofeither wheel 15 or 1'7 can take place only during the similar inactivityof the other wheel, since, in the showing, pawl 19 can be active withbut one wheel at a time. The two wheels provide essentially differenttiming activities, and the control of the start and ending of activitiesis therefore necessary to prevent concurrent advancing activities. Wheel15 is active in its advance only when the circuit-breaker is open, whilethe advancing activity of wheel 1'7 is limited to periods when thecircuit-breaker is closed, the service of wheel 15 being to determinehowlong the breaker shall remain open before attempting to reclose it,while wheel 1'7 serves to determine if the line conditions have changedto such an extent as to presumably ensure continued line activity undernormal conditions. It is obvious, of course, that if individual pawlsfor the wheels be employed, the same characteristic condition isprovided by rendering one pawl inactive to advance its wheel during theperiod when the other pawl is active in advancing the other wheel, thisbeing the teaching provided by the particular pawl arrangement shown, inwhich the double pawl is limited to activity with but one wheel at atime.

As will be understood, the system sets up the condition of a normalcycle which may or may not be completed, each cycle starting with theopening of the circuit-breaker and ending with the resetting operationprovided after the circuitbreaker has remained closed for a definiteperiod after re-closure. If but one cycle is required to restore theline to normal conditions, the cycle is completed from beginning to endafter once starting. If the abnormality persists, the cycle developmentis interrupted and a new cycle started, the elements, with the exceptionof the timing disk and the motor and cam being restored to the initialpositions prepared to perform its share in the cycle development. Ineffect, however, the only change with respect to the timing element atthe beginning of the second cycle is that it has not returned to itsinitial starting position to open the motor circuit-otherwise, the cycledevelopment is similar to the initial development, since the reclosingaction has simply substituted a second segment of the wheel 15 for thefirst .segment used in the initial cycle, the cycle development thusbeing similar to the first. The other changed condition is in the motorcircuit. At the start of the first cycle the motor and cam wereinactiveat the start of the second cycle, the motor and cam are inactive operation, having continued operation when the first cycle wasinterrupted.

This same condition will be present if the second cycle is interrupted,thus duplicating the initial cycle conditions withthe exception of thechanges indicated. With the third reclosure of the circuit-breakerineffective in presence of a continuance of the abnormality, the latteris considered as persistent and requiring manual attention, and when thecycle is then interrupted by contact of stops 33 and 34, no furtherattempts are made to produce automatic reclosing, the cycle remaininginterrupted until manual attention restores the various elements totheir in itial positions.

From this it will be seen that the elements are always ready to beginthe cycle when the line conditions call for its development, with thecycle of similar characteristic in each case, except for the changesindicated. Consequently, it is possible to provide a predeterminedvariation in the cycle development by the spacing of slots 31,permitting a variation in the time-length during which thecircuit-breaker will remain open in successive cycles. This is ofadvantage in that the second time-length can be made longer or shorterthan the first, and the third be varied from the others, etc.; this ismade possible by the fact that wheel 15 is not required to move to itsinitial position to develop the second cycle, so that the re-settingportion of the cycle can be interrupted at any point and yet serve toplace the system ready for the beginning of a second and third cycle, ifnecessary. With the permanent interruption present, the line obviouslyrequires manual attention and the completion of the cycle development isunnecessary.

This advantage is due in part to the fact that they motor-driven cam isitself no part of the timelength controlling structure-the cam simplyacts to impart movements to certain elements, and hence can be rapidlyrotated, so that its particular location at the instant of beginning thecycle is unimportant, it quickly reaching the position of the partswhich it is to actuate and starting the cycle. And the fact that themotor and cam continue operation after reclosing ensures an instantresponse by the cam if the second cycle is required. Because the cam canbe given these rapid movements, an additional advantage is presentthrough the fact that the hammer is immediately re-set, and there-closing movement of the circuit breaker is not only by motive powerbut is made quickly, giving assurance that the circuit breaker willremain in its open position the maximum length of time and then besnapped back to closed position. The cam itself thus presentscharacteristics of the inherent qualities of the motor as to timingaction; since the motor runs at a substantially uniform speed, the camcompletes its revolution in substantially uniform periods, ensuring thatthe step-by-step movements of the timing wheels will be at regularintervals of time, and thus ensuring greater accuracy in the timing.

As will be seen, the only solenoid controlling structure is the trippingsolenoids 30, these being the only control elements of the system whichare dependent for operation on the actual current flow; the two make andbreak points of the motor circuit are mechanical control elements whichsimply open and close the circuit mechanically. Make and break point 26is an intermittent closure, while point 37 is a sustaining closure, thetwo points being arranged in parallel, point 26 determining thebeginning of the initial motor operation and point 37 determining theending of this operation, the motor remains active during the interim;when the system reaches the "lock-ou condition of Fig. 5, both pointsare closed and remain so until the system is manually restored.

Wheels 15 and 17 are both latch-controlled to prevent returning actionafter pawl advance. These latches-36 and 38-are made active at propertimes, but rendered inactive when either wheel is to return to itsinitial inactive position. It is the control of these which determinesthe latter portion of the cycle development to ensure that wheel 15 willnot return to its initial inactive position and break the motor circuitbefore wheel 1'7 has completed its time-length activities to indicatethat the line conditions have returned to normal.

In these schematic views, a connection 45 connects bell-crank lever 9with the arm which carries pawl 19, thus indicating a synchronousmovement of the two elements to ensure that the pawl will be inactivewith the timing wheel 15 when the circuit breaker is closed and activewith this wheel when the circuit breaker is open, other than during theperiod in which the wheel is advanced the single step at the time thereclosing takes place, as heretofore pointed out.

As pointed out, the motor circuit remains open the initial contact atpoint 26 is made by the open circuit breaker. Assurance is thus had thatnone of the timing operations will begin in advance of opening of thecircuit breaker initially and ensuring that the system activities maynot be inaugurated excepting in presence of an actual break in the linecircuit provided by opening the circuit breaker. In addition, assuranceis had that the breaker will remain open for a definite time beforere-closing, the time of reclosing being positively determined by thetiming wheel 15, the actual reclosing movement being in immediateresponse to the entrance of end 13 into slot 31.

And it will be noted that while the motor circuit activity is initiallydependent on the opening of the circuit breaker, the close of motoroperation is not determined by the motor itself. The movement of arm 37to open the motor circuit is dependent on the return of wheel 14 to itsinitial position after having been moved out of such position, and themovement back to initial position is in a direction opposite to thedirection of movement of the wheel provided by motor activity. Hence,assurance is had that motor activity will continue until the system hasbeen completely re-set under the automatic operation, or until renderedinactive by the manual re-setting activities. In other words, the motoris rendered active to operate the cam 23, the movements of the latterbeing utilized to produce certain activities within the system by thesuccessive rotations of the cam, the number of which is immaterial sinceOther advantages are present, the above illustrating a few which are ofespecial importance.

What I claim is:

1. In automatic circuit breaker operating systems adapted for theprotection of line circuits, wherein abnormal conditions in the linecircuit will open the latter and concurrently establish amotor-operating circuit to produce activity of a motor, and wherein atrip mechanism rendered active by such abnormal conditions initiates theline circuit breaking action, a circuit breaker movable between open andclosed positions, a cam driven by the motor, mechanism including atoggle for supporting the circuit breaker in closed position andco-operative with the cam in re-closing the circuit breaker, an elementadapted to break the toggle when the trip mechanism is rendered active,a normally-inactive timing instrumentality rendered active by cammovements and co-operative with the breaker reclosing mechanism forcontrolling the movements of the latter into the path of cam travel,said instrumentality being operative to provide a succession of suchmechanism movements with predetermined time intervals therebetween, asystem re-setting instrumentality having a cycle to provide apredetermined maximum time period of activity with the cycle developmentprovided by cam movements and responsive to reclosing movements of thecircuit breaker, and mechanical operative connections between saidinstrumentalities to permit return of the timing instrumentality to itsinactive position upon the completion of the cycle of the re-settinginstrumentality.

2. A system as in claim 1 characterized in that the reclosing mechanismincludes a linkage of which the toggle forms a part, said linkagenormally supporting the circuit breaker in its closed position andpermitting opening of the circuit breaker when the toggle is broken,said linkage being collapsible under timing instrumentality control tostraighten the toggle and locate the linkage in the path of cam movementto reset the co-operative with the reclosure mechanism to permit acorresponding number of reclosures of the circuit breaker, the operativeconnections between the instrumentalities including a latch operativewith the ratchet wheel to prevent return movement of the wheel prior tolatch release by the re-setting instrumentality, said reclosingmechanism being operative to render the pawl inactive relative to thewheel when the circuit breaker is in closed position.

4. A system as in claim 1 characterized in that the re-settinginstrumentality includes a ratchet wheel, a pawl for advancing the wheelstep-bystep, an operating member for the pawl extending in the path oftravel of thecam andoperamovable intdand'out-of engagement with theratchet wheel and operative to prevent return of the latter when engagedtherewith, activity of the pawl and latch being determined by the reclQSing mechanism with the pawl inactive with the wheel during periodsof activity of the timing instrumentality.

5. In automatic circuit breaker operating systems adapted for theprotection of --line circuits,

wherein abnormal conditions in the lihehircuit,

will open the latter and concurrently establish a motor-operatingcircuit to produce activity oi. a motor, and wherein a trip mechanismrendered active by such abnormal conditions initiates the line circuitbreaking action, a circuit breaker for the line circuit, circuit-breakerposition-retaining and reclosing means including a collapsiblebreaker-supporting instrumentality normally active to retain the breakerclosed and movable to' collapsing position and permit breaker opening bytrip mechanism activity, a rotatable actuator driven by the motor, anormally-inactive reclosure timing instrumentality adapted to berendered active responsive to such abnormal line circuit conditions, aresetting instrumentality having a definite time period of normalactivity in succession to reclosing movements of the circuit breaker andadapted to complete such period in presence of normal line circuitconditions, said instrumentalities being co-related mechanically toproduce a normal succession of activities in which initial collapse ofthe supporting "instrumentality active for a predetermined period upontermination of which the supporting instrumentality is rendered activeby the rotating actuator to reclose the breaker and begin activity ofthe resetting instrumentality, the co-relation oi the instrumentalitiesbeing such that a persistence of the abnormal line circuit conditionsdiscontinues the activity 0! the resetting instrumentality and restoresthe latter to its initial position and repeats the normal succession ofactivities, said rotating actuator being active as the power source fortiming activities with the activity limited to intermittent co-operationduring instrumentality activity of the two timing instrumentalities toprovide step-by-step movements of such instrumentalities during timingactivities.

6. A system as in claim 5 characterized in that 100 tive in providingthe ratcheting cycle, a latch the breaker supporting instrumentalitymovements between breaker-supportingposition and collapsed position inwhich the breaker is in lineopen position, present the following cycle:initial collapse of the instrumentality by the trip mechanism,cooperation with the timing instrumentality for a predetermined periodto retain the supporting instrumentality inactive with the rotatingactuator during a predetermined period at the close of which the timinginstrumentality permits further collapse of the supportinginstrumentality to become active with the actuator to concurrentlyrestore the instrumentality to breaker supporting position and render itinactive with the timing instrumentality.

7. A system as in claim 5 characterized in that"the initial activity ofthe trip mechanism positions an element of the latter within the path ortravel of the rotating actuator to immediately restore the tripmechanism to operative position by actuator movement'while the circuitbreaker is in open position.

8. A system as in claim 5 characterized in that the timing movements ofthe timing instrumentality are rotative in constant direction away fromthe normally-inactive position of the instrumentality and include asuccession of stages of definite time characteristic, the activity ofeach stage being dependent upon and made in response to the previousinitial collapse of the supporting instrumentality.

9. A system as in claim 5 characterized in that the timing movements ofthe timing instrumentality are rotative in constant direction away fromthe normally-inactive position of the instrumentality and include asuccession of stages of definite time characteristic, the activity ofeach stage being dependent upon and made in response to the previousinitial collapse of the supporting instrumentality, return of the timinginstrumentality to its normally-inactive position being dependent uponand responsive to completion of the time period of activity of theresetting instrumentality.

10. A system as in claim 5 characterized in that the step-by-stepmovements of the timing and resetting instrumentalities are responsiveto rotative movements of the actuator and are nonconcurrent.

11. A system as in claim 5 characterized in that the timing movements ofthe timing instrumentality are rotative in constant direction away fromthe normally-inactive position of the instrumentality and non-responsiveto the resetting instrumentality activity, the return of the timinginstrumentality to normally-inactive position being dependent upon andresponsive to completion of the time-period of activity of there-setting instrumentality.

ROBERT S. SEESE.

